Hello! We have a nasty odor coming from the laundry sink cabinet area. I wonder if it is because it is seldom used allowing sewage smells in? Also there is a plumbing part in there I've never seen. (Though it could be common.) I have searched online through plumbing parts and haven't yet found it. Hopefully I've correctly attached the picture of this part.
Does anyone have ideas why it stinks and more importantly how I can fix it?
Thanks!